There are many circumstances when it is desirable to change the orientation of a sheet when feeding it from one piece of equipment to the other. This is especially true in the handling of business forms, whether single-part or multi-part forms, when it is desirable to act upon the forms in portrait mode in one piece of equipment, and landscape in another piece of equipment. There have been numerous mechanisms developed in the prior art for effecting rotation of sheets to effect this purpose; however, such sheet rotating mechanisms typically are mechanically complex and/or require a large surface to effect turning.
According to the present invention, a method and apparatus are provided for effecting the rotation of sheets, such as business forms, from landscape to portrait mode, or vice versa, or any orientation therebetween, in a simple yet effective manner, and with a minimum amount of space required to effect rotation.
The simple apparatus according to the invention comprises a conveyance surface on which a sheet, having a first orientation, travels in a first direction; first and second rollers for engaging the sheet traveling on the conveyance surface; first and second drive means, such as reversible motors (preferably D.C. stepper motors) operatively driving the first and second rollers, respectively, independently of each other; sensing means for sensing the leading edge of a sheet having a first orientation, with respect to the rollers, located just downstream of the rollers in the first direction; and control means for controlling speed and direction of rotation of the drive means in response to the sensing means. The rollers are spaced from each other in a second direction, generally transverse to the first direction, and their spacing in the second direction is relatively small, much less than the dimensions of a sheet being rotated. The control means preferably comprises a computer means for controlling the drive means to effect rotation of the sheet by driving the first rollers so that the tangential velocity thereof is in the first direction, and at a first speed, and by driving the second roller so that the tangential velocity thereof is in a third direction, opposite the first direction, and at the same speed as the first roller.
Typically, nip wheels, mounted on spring biased arms, are associated with the first and second rollers to hold the sheet in contact therewith. Also, a hold-down strap may extend between the rollers for facilitating engagement of the sheet with the conveyance surface. A pair of conveyor belts--mounted outside of the first and second rollers--preferably are provided for conveying the sheet in the first direction to the first and second rollers, and away from the first and second rollers, conveyance in the first direction taking place the entire time the apparatus is being operated.
The invention also contemplates a method of reorienting a sheet using first and second drive means which rotate first and second rollers independently of each other. The method comprises the following steps: (a) feeding the sheet, with a first orientation, in a first direction to a location adjacent the first and second rollers, at which the rollers engage the sheet; (b) at the location adjacent the first and second rollers, sensing the leading edge of the sheet; and (c) in response to step (b), controlling the drive means, to in turn control the speed and direction of rotation of the rollers, so that the rollers rotate the sheet to a predetermined second orientation, significantly angularly displaced from the first orientation. The rollers are spaced apart in a second direction, generally transverse to the first direction, and step (c) is preferably practiced by controlling the first drive so that the tangential velocity of the first roller is in a third direction, opposite the first direction; and the speed of rotation of the rollers is the same, merely in opposite directions. Step (c) is preferably practiced to move the sheet through an angle of approximately 90.degree., and the sheet is continuously conveyed in the first direction during the practice of steps (a) and (c). The location at which sensing takes place in step (b) is less than one-half the dimension of the sheet in the first direction when it has its first orientation, and under the sheet during rotation.
The term "sheet" as used in the present specification and claims encompasses single-part or multi-part documents of all construction, including business forms, and sheets of paper, film, plastic, or the like that are typically transferred from one piece of handling equipment to another, especially in the business forms art.
It is a primary object of the present invention to provide a simple yet effective method and apparatus for effecting rotation of sheets during transport from one piece of equipment to the other, and with a minimum of turning space required. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.